### Abstract

An algebraic preclosure for the turbulent flux of a passive scalar constituent is developed by using a spatial smoothing approximation for turbulent space-time correlations. The preclosure relates the flux to three statistical properties of the flow: (1) a scalar relaxation time associated with turbulent autocorrelations and a Green's function propagator; (2) the spatial gradient of the mean concentration; and, (3) a preflux correlation related to fluctuations in the instantaneous turbulent flux and to fluctuations in the instantaneous Reynolds stress. Previously reported DNS results for fully developed channel flows are used to represent the low-order statistical properties of the turbulence needed to evaluate the turbulent flux. The theory permits a priori predictions of the low-order statistical properties of a passive scalar constituent for a wide range of Schmidt numbers. Estimates of the Sherwood number are consistent with previous experimental observations.

Original language | English (US) |
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Title of host publication | Proceedings of the 1999 3rd ASME/JSME Joint Fluids Engineering Conference, FEDSM'99, San Francisco, California, USA, 18-23 July 1999 (CD-ROM) |

Publisher | American Society of Mechanical Engineers |

Pages | 1 |

Number of pages | 1 |

ISBN (Print) | 0791819612 |

State | Published - 1999 |

### Profile

### ASJC Scopus subject areas

- Earth and Planetary Sciences(all)
- Engineering(all)
- Environmental Science(all)

### Cite this

*Proceedings of the 1999 3rd ASME/JSME Joint Fluids Engineering Conference, FEDSM'99, San Francisco, California, USA, 18-23 July 1999 (CD-ROM)*(pp. 1). American Society of Mechanical Engineers.

**Passive scalar transport in fully developed channel flows.** / Petty, C. A.; Parks, S. M.; Weispfennig, K.

Research output: Chapter in Book/Report/Conference proceeding › Chapter

*Proceedings of the 1999 3rd ASME/JSME Joint Fluids Engineering Conference, FEDSM'99, San Francisco, California, USA, 18-23 July 1999 (CD-ROM).*American Society of Mechanical Engineers, pp. 1.

}

TY - CHAP

T1 - Passive scalar transport in fully developed channel flows

AU - Petty,C. A.

AU - Parks,S. M.

AU - Weispfennig,K.

PY - 1999

Y1 - 1999

N2 - An algebraic preclosure for the turbulent flux of a passive scalar constituent is developed by using a spatial smoothing approximation for turbulent space-time correlations. The preclosure relates the flux to three statistical properties of the flow: (1) a scalar relaxation time associated with turbulent autocorrelations and a Green's function propagator; (2) the spatial gradient of the mean concentration; and, (3) a preflux correlation related to fluctuations in the instantaneous turbulent flux and to fluctuations in the instantaneous Reynolds stress. Previously reported DNS results for fully developed channel flows are used to represent the low-order statistical properties of the turbulence needed to evaluate the turbulent flux. The theory permits a priori predictions of the low-order statistical properties of a passive scalar constituent for a wide range of Schmidt numbers. Estimates of the Sherwood number are consistent with previous experimental observations.

AB - An algebraic preclosure for the turbulent flux of a passive scalar constituent is developed by using a spatial smoothing approximation for turbulent space-time correlations. The preclosure relates the flux to three statistical properties of the flow: (1) a scalar relaxation time associated with turbulent autocorrelations and a Green's function propagator; (2) the spatial gradient of the mean concentration; and, (3) a preflux correlation related to fluctuations in the instantaneous turbulent flux and to fluctuations in the instantaneous Reynolds stress. Previously reported DNS results for fully developed channel flows are used to represent the low-order statistical properties of the turbulence needed to evaluate the turbulent flux. The theory permits a priori predictions of the low-order statistical properties of a passive scalar constituent for a wide range of Schmidt numbers. Estimates of the Sherwood number are consistent with previous experimental observations.

UR - http://www.scopus.com/inward/record.url?scp=0033400850&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033400850&partnerID=8YFLogxK

M3 - Chapter

SN - 0791819612

SP - 1

BT - Proceedings of the 1999 3rd ASME/JSME Joint Fluids Engineering Conference, FEDSM'99, San Francisco, California, USA, 18-23 July 1999 (CD-ROM)

PB - American Society of Mechanical Engineers

ER -